Haier GE APPLIANCES NF96US Service Manual page 25

Use the following steps to correctly size vent pipe diameter.
Furnace capacity?
1
Which termination?
2
Which needs most
3
elbows?
How many?
4
Desired pipe size?
5
What is the altitude?
6
Use Table 12A through
Table 13 to find max pipe
length or exhaust pipe
7
length. Includes all vent
pipe and elbows inside
and outside the house.
Figure 22. Vent Pipe Diameter Sizing
31-5000728 Rev. 0
040, 060,
080, 100 btuh
Standard or
Concentric?
See Table 11
Intake or
Exhaust?
2" or 3"
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